Fig. 2From: Drug-drug interactions and QT prolongation as a commonly assessed cardiac effect - comprehensive overview of clinical trialsPK fold change (Cmax) vs. PD fold change (QTc). Fold change = CmaxCombination/CmaxDrug and ΔQTcCombination/ΔQTcDrug; Negative values of QTc fold change represent QTc interval change for negative ΔQTc values as compared to baseline (QTc shortening for single drug, as well as for the combination)Back to article page